Sunday, March 22, 2009

This weekend, I was lucky enough to attend one day of the two day National Association of Rocketry annual conference. The location was in central CT. New York city rocketry people (me and probably one other guy) are very lucky this year; LDRS will also be very close.

The host, CATO #581, was the first club with which I ever launched (starting with an F50 about 10 years ago now).

The conference was held at the Wethersfield High School. A typical country public school: Huge and really well setup with dozens of classes, a pool, and even a greenhouse!

Only a few vendors were on hand. Many had raffles and sales. I was able to purchase 4.5 24mm F24 reloads for only $4! Obviously this is an incredible deal. (The .5 part refers to one extra propellant grain that didn't come with any other parts. Can't think of a good use for it right now.)

During the day, I attended many lectures:

Here one can see Jennifer Ash Poole leading the lecture: "Beginning Competition Rocketry." This was a fun talk on some of the basics of competition flying (something that I have never done.) Many NAR members are VERY serious about competition. At one point there was a huge debate about "misfire alley" and to be honest, I had no idea what that was.

These above images are from the next session: "Principles of Hybrid Propulsion." Kevin O'Classen, obviously an expert in hybrids because he seldom flies any other kind of motor, gave a great introduction to hybrid motors. The basics were indeed basic, but the talk quickly moved into specifics of safety, GSE (ground support equipment), and motor performance. The ignition systems were particularly interesting to me because I never knew how the nitrous flow was initiated while the fuel grain was heated at the same time. It is more complex than you may think! The investment in GSE is pretty substantial with hybrids, but over a few years a high power flyer will begin to profit because of the lower flight costs. Also, there is no need for the LEUP process even with M motors! One interesting project to watch is an upcoming 2 stage hybrid flight at LDRS. This appears to be the first of it's kind.

___--- Lunch ---___

The next talk was from CSXT team members. "First amateur rocket to space" was given by Eric Knight, Chet Bacon, Rod Lane, and Don Skinner. You should remember (if you are a rocketry person or a loyal reader) that the CSXT flew an S 50,150 to space in 2004. As previously stated, there is a lack of information about all CSXT space attempts. This matter came up during the presentation also. Again where are the articles and detailed reports that were on hand after the OuR and RRS Boosted Dart flights? The OuR project report was the article that got me started in the hobby. It is really important. Hopefully future projects will do a better job. The SS2S already appears to be doing this.

This CSXT talk did help give new information, if informally and only in little bits. The kind of information (and nice slideshow) that we would all want to see made public. Say on a certain rocketry web page, perhaps Rocketry Planet for example. Here are some little tidbits that were noteworthy:

The nose cone was part of the airframe and actually cut free by a linear shaped charge.

The rocket did not become sub-sonic until about 110,000 ft.

This was the first parachute ever deployed in space(?).

The launch crew heard the reentry sonic booms.

The booster fell off the chute around 50,000 ft.

CSXT from start to space spent at least $500,000.

The rocket hit about 8 RPS at burnout, and was very stable.

To test the electronics under spin, a large potters wheel was used.

Falconry transmitters were used for recovery (already knew this but they did stress just how good these things are for rocketry).

The rocket motor may have been only 1 or 2 sec. away from a cato due to burn through.

FAA approval was fairly easy to get; they liked a single monolithic rocket (simple = predictable.)

Next came the "Sugar Shot to Space" presentation by Robert Krech. This was the main draw of the day for me. Even more than CSXT, this project is fascinating. It takes on some very substantial challenges (.82 mass fraction!) and plans to use a totally new motor design: a single motor with two burn periods. This work, and the likely solid documentation, will be invaluable for all future space attempts. As with CSXT, I will only list the new information that came up. For more information, see my previous posts.

Lots of test videos for 75mm motors (static tests).

The use of white paint and later max. temp. tags to record thermal conditions.

Airframe at first expected to be titanium, but now may be carbon fiber gas pipe.

The burnout mass of the rocket will be on the order of 250 lbs! .82 mass fraction! This is a pro level mass fraction. If anyone were to combine this efficiency with APCP, 100 miles would be a reasonable target with the same airframe. SS2S is the biggest deal in amateur rocketry this decade. Let's see how they finish up.

Finally, I was able to attend a talk called "Materials in Sport Rocketry." Doc Damerau runs a web page that reports on some very intensive testing of many rocketry materials. Please visit this web page for more information. One shocking observation was that a 220 lbs. rated quick link carabineer failed at more than 2000 lbs!

Overall, for a small registration fee, I got lots of great lectures, 4.5 F motors for $4, and a free 24mm kit (see the Narcon logo for the kit they were giving out). This was a great time, and obviously anyone who did not attend this year should think about next time. Or at least come out to LDRS!